Radiation Protection Glossary

A radiation protection glossary for Radiation Protection Supervisors (RPS) and anyone interesting in radiation safety terminology. The glossary is a mixture of health physics terms, and phrases related to radiation legislation, transport, practical safety and similar.

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Electron volt

The electron volt (eV) is a unit used in Radiation Protection / Health Physics to describe the energy of Ionising Radiation. The value of the eV is derived from the energy required to accelerate an electron through a potential of 1 volt. In more familiar units the eV is approximately equivalent to 1.6 E-19 joules. In everyday use the units of KeV (or MeV) are used as the eV is obviously an extremely small quantity. In training we often say the eV represents the 'punch' that the ionising radiation has to do work (damage) and so can be related to hazard potential.

Physics is really nothing more than a search for ultimate simplicity, but so far all we have is a kind of elegant messiness

– Bill Bryson